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Tiger Beetles (tiger + beetle)

Distribution by Scientific Domains
Life Sciences100%

Selected Abstracts

Exceptional anoxia resistance in larval tiger beetle, Phaeoxantha klugii (Coleoptera: Cicindelidae)

PHYSIOLOGICAL ENTOMOLOGY, Issue 2 2003
Matthias Zerm
Abstract. The tiger beetle Phaeoxantha klugii inhabits Central Amazonian floodplains, where it survives the annual inundation period in the third-instar larval stage submerged in the soil at approximately 29 °C for up to 3.5 months. Because flooded soils quickly become anoxic, these larvae should be highly resistant to anoxia. The survival of adult and larval P. klugii was therefore tested during exposure to a pure nitrogen atmosphere in the laboratory at 29 °C. Adult beetles were not resistant (< 6 h). Survival of larvae decreased over time, maximum survival was 15 days, whereas time to 50% mortality was 5.7 days (95% confidence interval 3.8,7.9). Anoxia resistance was additionally tested in third-instar larvae submerged within sediment for 40 days before anoxia exposure in the laboratory. Anoxia resistance was greatly enhanced in these larvae, showing a survival rate of 50% after 26 days of anoxia exposure. It appears that the gradual flooding process and/or the submersion phase induced a physiological alteration, most probably a strong depression in metabolic rate, which requires some days for induction. The degree of anoxia resistance in larval P. klugii is remarkable among terrestrial arthropods worldwide, even more so considering the high ambient temperatures. The species is well-suited to serve as a model organism for studying the physiological mechanisms of anoxia and submersion resistance in terrestrial arthropods inhabiting tropical floodplains. [source]

Dry season ecology of riverine tiger beetles in Kruger National Park, South Africa

AFRICAN JOURNAL OF ECOLOGY, Issue 2 2008
Jonathan R. Mawdsley
Abstract The life cycles of many African species of tiger beetles (Insecta: Coleoptera: Cicindelidae) exhibit pronounced seasonality, with adult emergence and reproductive activity closely associated with seasonal rains. Anecdotal reports have suggested that adults of certain riverine tiger beetle species may be active during the dry season near perennial water sources. To test this hypothesis, fifteen sites along three perennial rivers in Kruger National Park, South Africa, were surveyed for tiger beetles in early September, 2006. Thirteen sites yielded adult beetles, with six species represented [Chaetodera regalis (Dejean), Cylindera disjuncta (Dejean), Habrodera nilotica (Dejean), Lophyra neglecta intermediola (Horn), Lophyridia fimbriata imperatrix (Srnka), and Myriochile melancholica (Fabricius)]. Microhabitat associations of adults of all six species and ovipositional/larval substrates of five of the six species are reported, along with observations on predatory and reproductive behaviours and the possible presence of an anti-predator chemical defence in C. regalis and L. fimbriata imperatrix. Résumé Le cycle vital de nombreuses espèces de Cicindèles (colépotères) africains présente une saisonnalité prononcée, l'émergence des adultes et l'activité reproductrice étant étroitement liées aux pluies saisonnières. Quelques rapports ont suggéré que les adultes de certaines espèces riveraines de cicindèles pourraient être actives en saison sèche à proximité de sources d'eau permanentes. Pour tester cette hypothèse, on a surveillé 15 sites le long de trois rivières permanentes dans le Parc National Kruger, en Afrique du Sud, au cours du mois de septembre 2006. Treize sites abritaient des cicindèles adultes, avec six espèces représentées, (Chaetodera regalis (Dejean), Cylindera disjuncta (Dejean), Habrodera nilotica (Dejean), Lophyra neglecta intermediola (Horn), Lophyridia fimbriata imperatrix (Srnka), and Myriochile melancholica (Fabricius). On a rapporté les associations d'adultes des six espèces et les substrats oviposition/larves pour cinq des six espèces dans les microhabitats, de même que des observations sur les comportements prédateur et reproducteur et sur la présence possible d'une défense chimique anti-prédateur chez C. regalis et L. fimbriata imperatrix. [source]

DNA-based identification of preys from non-destructive, total DNA extractions of predators using arthropod universal primers

MOLECULAR ECOLOGY RESOURCES, Issue 3 2006
JOAN PONS
Abstract Here, I show that prey sequences can be detected from DNA of tiger beetles of the genus Rivacindela using whole specimens, nondestructive methods, and universal cytochrome b primers for arthropods. BLAST searches of the obtained sequences against public databases revealed that the diet of Rivacindela is mostly composed of flies but also termites and other beetles. Accurate determination of order, family and even genus was achieved in most cases but rarely to species level. Results suggest that stored DNA samples extracted from whole predatory specimens could be an alternative to dissected gut contents as starting source for DNA-based dietary studies. [source]